The present invention relates to a method for transmitting data wherein the transmission bit rate is defined via the physical channel.
Owing, for example, to their being embedded in specific transmission formats, transmission channels in mobile radio systems only offer fixed data or, as the case may be, raw data transmission rates, while the data rates of different signals or applications differ therefrom. Such data rates consequently need to be mutually matched at an interface.
Matching of such type is described below using an example taken from the UMTS standard:
In the UMTS (Universal Mobile Telecommunication System), data packets are sent to a mobile station (UE=User Equipment) on the high-speed downlink shared channel (HS-DSCH). The associated control information, such as the channelizing codes used for the HS-DSCH and the modulation scheme, such as QPSK (Quadrature Phase Shift Keying) or 16QAM (16 Quadrature Amplitude Modulation), is sent on the high-speed shared control channel (HSSCCH). Such control information or, as the case may be, this load data is linked to identification information so that the receiving mobile station can recognize that the information on the HS-SCCH is intended for it. “Masking of the data” is a term also used in this connection. Prior to linking, both load data and identification data undergo coding and, in each case, immediately ensuing rate matching.
This process is highly complex, however, which is disadvantageous particularly where the mobile radio device is concerned inasmuch as such coding and rate matching processes are cancelled again in order to arrive at the original (load) data.
Proceeding from this prior art, the present invention seeks to carry out rate matching in a less complex manner in one channel used jointly by a number of communication participants.